Conventional stock welding material is mainly made of rare and noble metals, such as nickel, chromium, niobium, cobalt, etc., as main ingredients, and of carbon as an additional component. The prior art has the defects that the source of the material is insufficient and that the cost is high. On the other hand, carbon is used for enhancing the hardness. However, cracks appear when the hardness reaches HRC 58. Even if quenching processes are performed to enhance the hardness, the hardness may only reach to HRC 58 and the failure rate is high, which results in waste. As for cold rolled stock welding material, such as steel, its hardness should reach over HRC 60. Some American specialists drew a conclusion that it is impossible for stock welding material to reach HRC 60. Soviet experts also had an opinion that it is normal and certain for stock welding to produce cracks when its hardness reaches HRC 60.
A welding wire which is made of tungsten carbide, available from Stellite Welding Material Co. Ltd. (Shanghai), has a hardness of only HRC 52-58. Cracks appear when the hardness is higher.
A stock welding flux cored wire made of tungsten carbide, available from Jingluo Welding Wire Company in Luohe city of Henan Provence in China, of the type TO-8705, has a hardness of HRC 52-58. Cracks appear when the hardness is higher.
Moreover, the hardness of the two kinds of stock welding material mentioned above is enhanced by quenching, but it still can not reach HRC 60, their maximum hardness being only HRC 58. The quenching time is long and electricity consumption is high, as a result, the cost is high. This kind of stock welding material can only be used for hot rolled processes. As for repairing cold rolled processes, there is still no suitable stock welding material so far.